Equipoising mechanism



July 16, 1935. G. CARWARDINE EQUIPOISING MECHANISM 4 Filed Sept. 14, 1934 M72) Mm Patented July 16, 1935 l 2,008,093

UNITED STATES PATENT OFFICE lllQUIPOISING MECHANISM George Carwardine, Bath, England, 'as signor of. one-half to Herbert Terry & jSons Limited,

'Redditch, England, a British company Application September14, 1934, Serial No. 743,944 In Great Britain October 7, 1933 4 Claims. (Cl. as-97) This invention relatesto improvements in conto k p t s lever f poised i p rman t p su nection with the mounting of mirrors, pictures, Contact With the D o e h on he S rutphotographs, and the like, and ha for it b t The abutment recess g is substantially straight the provision of equipoising mechanism whereby and parallel to a line through the centres of the 5 the mirror or the like can be readily tilted to any l s or roller h and t p v t and s at d be- 5 desired angle without liability to collapse due to ween terminal stops Z and m, and since the pivot disturbed equilibrium, e and the peg or roller h are at equal distances A mirror or the like can b supported on from the joint 0, it follows that the poised lever) table by providing it with a, rea t t, b t if will not be displaced from its normal vertical set- 10 this strut be hinge-d to permit of tilting at vati s what v m y be h a iv a u ar d p s l0 rious angles, the mirror or the like will only retiOhS 0 the bracket it a d Strut bmain stable in settings in which the angle be- The Spring is Connected be we n the br ck t tween the strut and the vertical is less than 11 and poisedlevei'f in Such a'mahher that When the angle of irietion between the strut and the h mirror d is p y t l d a d the centre 15 table. A setting at any greater angle will overof av y o the mountilosr a d r r app a h s come the friction and the support will collapse. its highest point (Figure then e lihebf According to the present invention, in order force f h Spring ppr a s a n p n to permit of the stability oi'a strutted mirror or ro h t l w r p in f nn c ion a and the like in settings outside the angular limits rethrough the P v s pp c t an pp ferred to, a coiled tension spring is connected bepo of unstable equilibrium being limited by 20 tween the back of the mirror and an anchorage t p d the approach to the lower point on a poised lever pivotally connected to the ting bei g e s limited y the p The back of the mirror in pressure cooperation with r e f the Spring is va d y adjusting its the strut, the poised lever being so disposed in re- Poi t O nc a e k o t e p s d lever flation to the strut as not to rotate in a vertical, The lower ends of the bracket or and strut b' plane as the mirror tilts, and the spring being which contact with the table are. rounded or preferably characerized in that its tensional pull are preferably fitted with rollers to facilitate is proportionate to its length. horizontal displacement, the strut b having for In order that the invention may be clearly unexample a single roller 12, and the bracket a bederstood and readily carried into practice, refing provided with a spaced pair of rollers o to en- 30 erence may be had by way of example to the acsure lateral stability. companying drawing, in which:- The spring 1' will generally be such' as to have I Figure l is a side elevation of a strutted mirror a large measure of pre-set strain, determined having the improvements applied, the mirror bemainly according to the closed coil length of the ing shown in a high angular setting. spring, this having the eiiect that the force ex 35 Figure 2 is a rear elevation of the mirror in erted by the spring is proportionate toits length the setting shown in Figure 1. and not to its measure of extension.

Figure 3 is a side. elevational view correspond- The lever f can be arranged to be poised in ing to Figure l but showing the mirror in a lower a horizontal or other angular position by a suit- 40 angular setting. V

In the embodiment illustrated an attachment peg or roller it, always provided. that the said bracket a and a strut b are pivotally jointed topivot e and the peg or roller h are equidistant gether at 0 so as to form an inverted V structure from the joint c. of which the legs from the joint downwards are It will moreover be appreciated that the inof equal length. The bracket a, to which is atvention can be applied in a variety of ways to 45 tached the mirror d, is extended above the joint 0, serve many useful purposes in addition to the and to this extension is pivoted at e a dependently equipoising of mirrors and the like, such for expoised lever 1 having on its inner edge an interample as in connection with artists and scholastic mediate recess 9! forming an abutment for a peg easels, music and reading stands, and. the like.

5 or roller It provided on the strut b at a distance What I claim as my invention and desire to below the joint 0 equal to the distance at which secure by Letters Patent is: the poised lever f is pivoted at e above the joint 0. 1, An equipoising mechanism for ensuring the A c iled t ns n sp in i s n w nn t d at a stability of a strutted mirror, stand, or the like, to the lower end of the bracket a andanchored at in various angular, settings, comprising a strut k to the lower end of the lever 7, thereby serving pivotally jointed to the back of the mirror, a 55 able dispositon of its pivot c in relationto the 40 poised lever pivoted to the back of themirror .above the pivotal joint for said strut, and a coiled claim 1, in which said spring is such that the force exerted by it is proportionate to its length.

8. An equipoising mechanism fortensuring the stability of a strutted mirror, stand, or the .like in various angular settings, 'and vvhich comprises a bracket attachable in an upright ,position to the back of the mirror or the like, a strut pivotally' jointed to an upper lp'art of said 'bracket, a

below the pivotal joint for the strut, 5a poised lever pivoted to an upper extension of said brack- 'et above the pivotal joint for the strut, and a coiled tension spring connected between the'back of the mirror or the like and an anchorage point on said poised lever so as to hold the lever in pressure contact with'the peg or roller on the strut, the peg'or roller and the poised lever pivot being located at equal distances from the piv otal joint forthe strut so that the poised lever will not rotate in avertical plane as the mirror or the like is tilted.

.-An equipoising mechanism as specified in claim 3, in which said poised lever intermediate its ends is formedwit-h a recess, the ends of said recess constituting stops'adapted to engage said peg or roller thereby limiting the angular move- *-ments of-said strut. peg or roller provided on said strut at-a point GEORGE CARWARDINE. 

